Error CS1061 - List.Item[Int32] Property

Question

This problem is very similar to this question, this question, this question (same error, different source class), and this question (same error, different reason).

After compiling my programs in a project to check for errors, I got the following CS1061 error:

Entity.cs(291,24): error CS1061: 'List<Entity>' does not contain a definition for 'Item' and no extension method 'Item' accepting a first argument of type 'List<Entity>' could be found (are you missing a using directive or an assembly reference?)

Entity.cs is the name of the file where the error occurred, and said error occurs in the Load() function, shown below:

public void Load(){
    /*
        Try to spawn the entity.
        If there are too many entities
        on-screen, unload any special
        effect entities.
        If that fails, produce an error message
    */
    try{
        if(EntitiesArray.Count >= EntitiesOnScreenCap){
            if(this.Type == EntityType.SpecialEffect)
                Unload();
            else
                throw null;
        }else
            //Place the entity in the first available slot in the array
            for(int i = 0; i < EntitiesArray.Capacity; i++)
                if(EntitiesArray.Item[i] == NullEntity)
                    EntitiesArray.Item[i] = this;
    }catch(Exception exc){
        throw new LoadException("Failed to load entity.");
    }
}

The error happens on these lines (lines 291 & 292):

if(EntitiesArray.Item[i] == NullEntity)
    EntitiesArray.Item[i] = this;

NullEntity is a field of type Entity, and this is also of type Entity.

EntitesArray is a List<Entity> and, therefore, should have an Item[] property, according to the MSDN documentation here.
Entity does not have a method or array named Item.

Declaration at beginning of class Entity:

public static List<Entity> EntitiesArray;

Instantiation in a method in Entity that is guaranteed to run only once:

EntitiesArray = new List<Entity>(EntitiesOnScreenCap);

Field EntitiesOnScreenCap is an int equal to 200.

This is included at the highest scope (before the namespace), so there should not be any problems regarding this:

using System.Collections.Generic;

What is causing this CS1061 error, and how can I fix it?

score 2 · Accepted Answer · answered Jul 07 '18 at 04:17

2

The Item property isn't a normal property in C#. It is a way to indicate that you can use an indexer to reference a specific item from the Enumerable. To use it, you just put the indexer value inside square brackets:

EntitiesArray[i]

answered Jul 07 '18 at 04:17

Elezar

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Oh, so it's like using a regular array in that respect. – absoluteAquarian Jul 07 '18 at 04:19
The syntax is the same, and in the case of a List, yes, it basically works the same way. However, it's possible to have non-integer indexers, and they can even be overloaded. For example, a `NameValueCollection` has both an int and a string indexer. So you can reference an item either by position or name. For example, both `nvc[0]` and `nvc["FirstName"]` are valid for a `NameValueCollection` named `nvc`. – Elezar Jul 07 '18 at 04:40

Error CS1061 - List.Item[Int32] Property

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